P0700 CODE - TRANNY TROUBLES

2001 Chrysler Town and Country

Transmission problem
2001 Chrysler Town and Country 6 cyl Two Wheel Drive Automatic 88,000 miles

Hi,

I used my wife's van yesterday and it was fine. This morning, it's broken. Obviously, I'm suspect since I was the last to use it. Lol but I've been trying to get some info and thought you guys could help. Here are the specs

Here's what's happening - Wife went to drive it this morning. It was 'bucking' during downshifting only into 2nd and 1st gear. No issues accellerating. She brought it back, and it was low on fluid. I topped it off. Fluid didn't appear burned or red/brown. Still Bright. I drove it around, and felt the bucking. While driving it all the sudden lost all gears but 2nd (limp mode) but after shutting it off, I had the gears all back (out of limp mode) but it was bucking downshifting into 2nd and 1st gear again. Then it went back into limp mode.

Here's what I've done - Pretty much nothing. It's sunday. But. I thought maybe it was bucking because it was low on fluid, and the P0700 code needed to be cleared out. I disconnected the battery for about 30 min, reconnected it, and without even starting it, and just turning the key fwd/back 3 times, the P0700 is there. Didn't even start it.

My question is shouldn't the vehicle need to be driven? I thought that the sensors in the Transmission sent info (above or below spec) to the TCM and it interpreted it and sent to the PCM to put the CIL on or off. Or some variation of that. Would the 0700 being there after clearing codes indicate that the TCM is so broken, it's picking it up immediately, without driving it?

I'm a novice, and don't pretend to do the good work you guys do, this is just a product of knowing a LITTLE about cars (hey, I own a 91 Bronco - you tend to learn a little owning that hog) and I've been googling all day.

P0700 is just an information code
and it is that TCM have codes and requested check engine light on
most repair shop can help in get the tcm codes
it should points to what is the problem
if to start should do speed sensors 1st

Sorry for the delay in getting back here. Had some personal issues come up and the van had to sit for a while. I did get it up to one of the local transmission shops yesterday.

He said he wasn't getting any codes from the TCM, so he cleared the P700 code, drove it around for 10-15 min and it was fine. He said he felt a slight 'flair' going from 3rd - 4th. He drove it around more and then the vehcile went into limp/safe mode again. He sait it gave a P700 code, and now the TCM is telling him " 4th Gear Ratio Error" He said he checked the CVI (Clutch Value Index) data, and it all looked within spec. He said to further diagnose it, he'd need to remove the transmission, crack it open and go through it.

He said he can give me a price once he finds the internal issue. He also said that if he finds the problem, and I don't like the price, he'll put the transmission back together, and in the vehicle for $389.

My question - With ONLY a P700, and nothing else showing, could the issue possibly be an input/output sensor, or would that have shown up in the Van's computer. Is it possible that just having a P700 is not internal? I originally researched and saw the TCM's DO go bad, but he's saying it's fine because he's not getting some BIOS error when reading the codes.

He didn't give me any codes (not sure if that was purposely or not). All he told me is that it gave him a " 4th gear ratio error" Kinda baffled at the need to drop a transmission and crack it based on him telling me it drove fine for 15-20 min after he cleared the codes till it threw the 0700 code again, and that everything else seemed to be 'in spec'

Would a sensor necessarily give a PCode? I think I read that there was a PCode associated with a bad input/output sensor. But the odometer never gave anything other than P0700 (and I think an O2 sensor that just went bad)

Let me ask you a quesiton about this. Prior to taking it up to them, I had removed the battery cables, and let it sit to clear the code from the car.

Prior to even starting the vehicle, the P0700 had come back.

Would you think the TCM is the likely culprit in that situation?

Previously you mentioned P0700 was informational, but what you posted seems to imply that if you clear the codes, and P0700 comes back (even if it's the only code) then it's a faulty TCM unless I read that wrong.

Is removing the battery cable sufficient enough to clear the P0700 and if so, if it came back without even starting the car, is that normal? I would have thought it would have had to be driven. I've got no way to verify what he claimed (as far as clearing it and then it coming back 15-20 min of driving later). In my driveway, I removed the battery cables, reconnected and it came back.

He did say initially there were no codes in the TCM so he cleared it, and when P0700 came back THEN he saw this " 4th gear" code.

Could he be blowing smoke up my TCM maybe?

EDIT - The more I think about it, maybe the P0700 did come back when I started it, but it DEFINITELY came back without me shifting the shift lever or driving it.